The present invention relates generally to integrated circuits, and relates more specifically to the measurement of temperature on integrated circuit chips.
The establishment of temperature-dependent transistor mobility variability in complementary metal-oxide-semiconductor (CMOS) chips relies heavily on accurate knowledge of on-chip temperatures, which typically vary across the chip. Temperatures across a chip may cause delay changes, which consume the chip's timing margin and may cause serious circuit-limited delay variability.
To date, there are few reliable methods for capturing high-resolution, dynamic on-chip temperatures. Some conventional solutions require the placement of additional structures (such as ring oscillators) on the chip, which reduces the area and power available to other chip components. Conventional imaging-based techniques (such as infrared imaging) tend to capture temperature in a time-averaged manner and at relatively low resolution. Other conventional methods, such as those involving measuring the thermionic emissivity of fluorescing materials applied to the chip, are not economically efficient for use with large numbers of machine states.
Thus, there is a need in the art for a fine resolution, highly dynamic method and apparatus for measurement of across-chip temperatures.